Unit 2 Pretest

A linear regression model is best described as which of the following?

• A spooky chart of ghosts haunting data points

• An equation showing the linear relationship between two data sets

• A map of ghost sightings (a scatter plot)

• A creepy number showing how close data sets are related

Given the data pairs x (# Trick-or-Treaters) | y (Pieces of Candy): (0,0), (5,20), (10,40), (15,60), what is the slope of the linear function relating y to x?

• 20

• 4

• 5

• 0

A scatter plot is…

• A graph showing ghostly dots floating around randomly

• A bar graph showing how tall the candy stacks are

• A graph that shows the relationship between two sets of data

• A pie chart of pumpkin pies

When the slope is negative, the line travels…

• Upward left to right

• Downward left to right

• Flat like a horizontal line

• Straight up vertically

Which graph represents the equation y = -3x + 2? (Use the provided graph options.)

• The graph where the line crosses the y-axis at 2 and falls 3 for every run of 1

• The graph where the line crosses the y-axis at -4 and falls 2 for every run of 3

• The graph where the line rises 3 for every run of 1 and crosses the y-axis at 2

Choose the scatter plot that has a negative correlation (as one variable increases, the other decreases).

• Points trend upward from left to right

• Points form no clear trend

• Points trend downward from left to right

• Points lie exactly on a horizontal line

Each new figure in a pattern adds 2 pumpkins. Which equation models the total pumpkins y in figure number x, assuming the first figure has 0 pumpkins?

• y = 2x

• y = x + 2

• y = 2x + 1

• y = 2x - 2

In the pumpkin pattern where each figure adds 2 pumpkins and the first figure starts at 0, how many pumpkins are in the 31st figure?

• 31

• 60

• 62

• 64

Graph y = -2/3 x - 4. Which statement is true about its intercepts?

• y-intercept is -4

• x-intercept is -4

• y-intercept is 4

• The line passes through (0,4)

Using y = 420 - 6.5x, what is Dracula’s balance after 3 months?

• $413.50

• $400.50

• $420.00

• $399.00